New monoazodyestuffs



l atented Sept. 22,

UNrrED STATES WINFRID HEN'IRICH, or WIESDORF-ON-THE-RHINE;AND rwnonn xnocnn-or LEVER- KUSEN-ON-THE-RHINE, GERMANY, ASSIGNORSTO GENERAL ANI LINE OF NEW YORK, N. Y., A. CORPORATION OF DELAWARE a WORKS; INC

NEW monoAzonynsrunrs No Drawing. Application filed May 7, 1929, Serial n;3 1,254, and-in Germany May 14,1928.

The present invention relates to new monoazo-dyestuffs more particularly it relates to azo-dyestuifs of the probable general formula om-Qrh amino-naphthalene-sulfonic acid of which the alkyl residue. contains three to five carbon atoms.

Our new dyestuffs are in the dry pulverized form dark metallic lustrous powders, in the form of their alkali metal salts soluble in water with a violet to blue coloration. From an acid bath they dye wool even blue to violet shades of good fastness to washing, fulling and light. The dyeings on wool can be discharged whereby clear White effects are obtainable which are fast to light. On reduction with stannous chloride and hydrochloric acid the dyestuffs yield 1.4-diaminobenzene- 2-sulfonic acid and l-amino-2-alkyl-aminonaphthalene-sulfonic acid.

Our invention is illustrated by the following example, but is not restricted thereto, the parts being by weight:

EwampZe.-235 parts of the ammonium salt of l-nitro-1-amino-benzene-2-sulfonic acid are diazotized in the usual manner, coupled with 27 9 parts of 2-isobutylamino-naphthashort time, the dyestuff, having in the free state the following formula:

addition of sodium carbonate, salted out, filtered and dried. The dyestufi' dyes wool from an acid bath even bluish violet shades of good fastness to Washing, fulling and light. The dyeings can be discharged and the discharge points are fast to light and water.

If in the above example the 2-iso-butylamino naphthalene-7-sulfonic acid is substiwherein R standsfor an alkyl group contaming three to five carbon atoms, being in the dry pulverized form dark metallic lustrons powders, in the form of their alkali" metal salts soluble in water with a violet to blue coloration, dyeing wool from an acid bath even blue to violet shades of good fastness to washing, fulling andlight. 1

2. As a new product the monoazo-dyestufi of the probable formula:

being in thedry pulverizedf orm a dal k metallic lustrous powder, in the form of its 5 Washing, fulling and light.

alkali metal salts soluble in water with a violet coloration,idyeing wool'from an aeidbath even bluish violet shadesof good, fastness to In testimony whereof We have hereunto set our hands.

WINF RID HENTRICH. [L. s.] RUDOLF KNOCHE. i [1,. 8.] 

